Hand washing




Hand washing, also called hand hygiene, is the process of cleaning the hands with soap or handwash and water to eliminate bacteria, viruses, dirt, microorganisms, and other potentially harmful substances. Drying of the washed hands is part of the process as wet and moist hands are more easily recontaminated. If soap and water are unavailable, hand sanitizer that is at least 60% alcohol in water can be used as long as hands are not visibly excessively dirty or greasy. Hand hygiene is central to preventing the spread of infectious diseases in home and everyday life settings. Meta-analyses have shown that regular hand washing in community settings can significantly reduce respiratory and gastrointestinal infection.
The World Health Organization recommends washing hands for at least 20 seconds before and after certain activities. These include the five critical times during the day where washing hands with soap is important to reduce fecal-oral transmission of disease: after using the toilet, after cleaning a child's bottom, before feeding a child, before eating and before/after preparing food or handling raw meat, fish, or poultry.
When neither hand washing nor using hand sanitizer is possible, hands can be cleaned with uncontaminated ash and clean water, although the benefits and risks are uncertain for reducing the spread of viral or bacterial infections. However, frequent hand washing can lead to skin damage due to drying of the skin. Moisturizing lotion is often recommended to keep the hands from drying out; dry skin can lead to skin damage which can increase the risk for the transmission of infection.

Steps and duration

The United States Centers for Disease Control and Prevention recommends the following steps when washing one's hands for the prevention of transmission of disease:
  1. Wet hands with warm or cold running water. Running water is recommended because standing basins may be contaminated, while the temperature of the water does not seem to make a difference, however some experts suggest warm, tepid water may be superior.
  2. Lather hands by rubbing them with a generous amount of soap, including the backs of hands, between fingers, and under nails. Soap lifts pathogens from the skin, and studies show that people tend to wash their hands more thoroughly when soap is used rather than water alone.
  3. Scrub for at least 20 seconds. Scrubbing creates friction, which helps remove pathogens from skin, and scrubbing for longer periods removes more pathogens. According to the CDC, scrubbing with soap for at least 20 seconds is necessary to remove most germs effectively, regardless of water temperature.
  4. Rinse well under running water. Rinsing in a basin can recontaminate hands.
  5. Dry with a clean towel or allow to air dry. Wet and moist hands are more easily recontaminated.
The most commonly missed areas are the thumb, the wrist, the areas between the fingers, and under fingernails. Artificial nails and chipped nail polish may harbor microorganisms.

When it is recommended

There are five critical times during the day where washing hands with soap is important to reduce fecal-oral transmission of disease: after using the toilet, after cleaning a child's bottom, before feeding a child, before eating and before/after preparing food or handling raw meat, fish, or poultry. Other occasions when proper hand washing techniques should be practiced to prevent the transmission of disease include before and after treating a cut or wound; after sneezing, coughing, or blowing your nose; after touching animal waste or handling animals; and after touching garbage.In healthcare settings, the WHO also recommends "Five Moments for Hand Hygiene"" before patient contact, before aseptic tasks, after exposure to body fluids, after patient contact, and after contact with patient surroundings.

Public health

Health benefits

Hand washing has many significant health benefits, including minimizing the spread of influenza, COVID-19, and other infectious diseases; preventing infectious causes of diarrhea; decreasing respiratory infections;
and reducing infant mortality rate at home birth deliveries. A 2013 study showed that improved hand washing practices may lead to small improvements in the length growth in children under five years of age. In developing countries, childhood mortality rates related to respiratory and diarrheal diseases can be reduced by introducing simple behavioral changes, such as hand washing with soap. This simple action can reduce the rate of mortality from these diseases by almost 50%. Interventions that promote hand washing can reduce diarrhea episodes by about a third, and this is comparable to providing clean water in low income areas. 48% of reductions in diarrhea episodes can be associated with hand washing with soap.
Handwashing with soap is the single most effective and inexpensive way to prevent diarrhea and acute respiratory infections, as automatic behavior performed in homes, schools, and communities worldwide. Pneumonia, a major ARI, is the number one cause of mortality among children under five years old, taking the lives of an estimated 1.8 million children per year. Diarrhea and pneumonia together account for almost 3.5 million child deaths annually. According to UNICEF, turning handwashing with soap before eating and after using the toilet into an ingrained habit can save more lives than any single vaccine or medical intervention, cutting deaths from diarrhea by almost half and deaths from acute respiratory infections by one-quarter. Hand washing is usually integrated with other sanitation interventions as part of water, sanitation, and hygiene programmes. Hand washing also protects against impetigo which is transmitted through direct physical contact.

Adverse effects

A small detrimental effect of handwashing is that frequent hand washing can lead to skin damage due to the drying of the skin. A 2012 Danish study found that excessive hand washing can lead to an itchy, flaky skin condition known as contact dermatitis, which is especially common among health-care workers.Frequent use of alcohol based hand sanitizers can also contribute to skin irritation and dryness, although this effect may be reduced by formulations that include moisturizers.

Behavior change

In many countries, there is a low rate of hand washing with soap. A study of hand washing in 54 countries in 2015 found that on average, 38.7% of households practiced hand washing with soap.
A 2014 study showed that Saudi Arabia had the highest rate of 97%; the United States near the middle with 77%; and China with the lowest rate of 23%.
Several behavior change methodologies now exist to increase uptake of the behavior of hand washing with soap at the critical times.
Group hand washing for school children at set times of the day is one option in developing countries to engrain hand washing in children's behaviors. The "Essential Health Care Program" implemented by the Department of Education in the Philippines is an example of at scale action to promote children's health and education. Deworming twice a year, supplemented with washing hands daily with soap, brushing teeth daily with fluoride, is at the core of this national program. It has also been successfully implemented in Indonesia.

Recent Global Initiatives (2020-present)

In recent years, hand hygiene has remained central to global infection prevention efforts, particularly following the COVID-19 pandemic. The World Health Organization reported in 2023 that fewer than 60% of health-care facilities in low- and middle-income countries have adequate hand hygiene resources at points of care. To address this gap, the WHO and UNICEF launched the Hand Hygiene for All initiative in 2020 to promote integration of hand hygiene into national health policies. Early research emphasized the critical role of hand hygiene in preventing health care–associated infections. Sustained behavioral interventions and system-level investments remain essential to improve compliance and reduce health care–associated infections worldwide. Improving hand hygiene practices is also a key target within the WHO Global Patient Safety Action Plan 2021–2030, which aims to reduce health care–associated infections and antimicrobial resistance.
In 2025, the World Health Organization introduced updated hand-hygiene recommendations emphasizing the need for reliable access to water, soap, and alcohol-based hand rubs with safe grey-water disposal; clear guidance on when, why, and how hand hygiene should be performed; and a supportive physical and social environment that ensures facilities are accessible and convenient.

Substances used

Soap and detergents

Removal of microorganisms from skin is enhanced by the addition of soaps or detergents to water. Soap and detergents are surfactants that kill microorganisms by disorganizing their membrane lipid bilayer and denaturing their proteins. It also emulsifies oils, enabling them to be carried away by running water.

Solid soap

Solid soap, because of its reusable nature, may hold bacteria acquired from previous uses. A small number of studies which have looked at the bacterial transfer from contaminated solid soap have concluded transfer is unlikely as the bacteria are rinsed off with the foam. The CDC still states "liquid soap with hands-free controls for dispensing is preferable".

Antibacterial soap

s have been heavily promoted to a health-conscious public. To date, there is no evidence that using recommended antiseptics or disinfectants selects for antibiotic-resistant organisms in nature. However, antibacterial soaps contain common antibacterial agents such as triclosan, which has an extensive list of resistant strains of organisms. So, even if antibiotic resistant strains are not selected for by antibacterial soaps, they might not be as effective as they are marketed to be. Besides the surfactant and skin-protecting agent, the sophisticated formulations may contain acids as pH regulator, antimicrobially active benzoic acid and further skin conditioners.
A 2007 meta-analysis from the University of Oregon School of Public Health indicated that plain soaps are as effective as consumer-grade anti-bacterial soaps containing triclosan in preventing illness and removing bacteria from the hands. Dissenting, a 2011 meta-analysis in the Journal of Food Protection argued that when properly formulated, triclosan can grant a small but detectable improvement, as can chlorhexidine gluconate, iodophor, or povidone.